Railway crossing signal control circuits



Sept. 22, 1931. A. E. HUDD ET AL 1,324,207

RAILWAY CROSSING SIGNAL CONTROL CIRCUITS Filed Sept. 29, 1928 I'LW.'TIFHlfred E. Hudd Harry E. Hershey Patented Sept. 22, 1931 "UNITED "STATESPATENT OFFICE ALFRED E. HUDD, OF EVANSTON, AND HARRY E. H ERSHEY OF OAKPARILILLINOIS,

ASSIGNOR-S 10 RESERVE HOLDING COMPANY, OF KANSAS CITY, MISSOURI, A COR-PORATION OF DELAWARE RAILWAY CROSSING SIGNAL CONTROL CIRCUITSApplication filed-September 29, 1928. Serial No. 369,173.

copending Hudd application S. N. 139,794,

The present invention relates in general to railway crossing signal.control circuits, that is, to control of. signals or other safetyapparatus located at intersections of railways and highways and servingto warn those using the highway when a train is approachwhile Fig. 5diagrammatically illustrates the relation between a locomotiveor vehiclecarried magnet and a. trackside relay operable thereby for controllingthe circuits of theequipment referred to. x I I I In Fig. 1, theapparatus and circuits are arranged for a tracKway onwhich traflic isalways in the same direction, Fig. -2 illustrates circuitsand apparatusfor a trackway wherein the .traific is ordinarilyinone direction, butwherein the signal is properly controlled if the train approaches thesignal and then backs up instead of proceeding; Fig. 3

illustrates circuits and apparatus for con trolling .the signal of atrackway wherein traiiic moves in both directions; Fig. 4 illustrates analternative arrangement for a trackway wherein the-traffic is in onedirection only and wherein the signal control circuit is under controlof a line relay; while Fig. 5

diagrammatically illustrates-a train carried .electromagnet for use incontrolling the operation of the circuits and apparatus d18- closed inFigs. 1 :to-i, inclusive. This figure also diagrammaticallyillustrates atrack relay placed in. a non-magnetic box alongside the track, in itsproper position relative to. the train carried magnet.

The signal control equipment ofFig. 1 confiledv Oct. 6, 1926, andconsists of, a pair of pickup inductor plates 1 and 2,-having pole pieceextensions 3 and 4; an armature 24 with an associated contact;apermanent magr' net 75; and of an armature restoring winding 28.Thearmature .is pivoted at a point near one pole of the permanentmagnet,while the pole pieces 2and 3.are closely associated with the other poleof the magnet. .VVi-th this con-- struction and arrangement of apparatusthe armature 24 is magnetically biased to either of the pole pieces-3 or4 to which ithas been moved or attracted. The winding .28 about the polepiece 4 is for moving thearmature .2iinto association with the polepiece 4 after it has been operated into association with the pole piece3.

The relay 22,. so far as structure is concerned, is the same as relay21. Thearmature is biased towards pole piece 5, however. This isaccomplished inanyofseveral ways, i. .e., the contact associated withthe armature 23, .niay-be located so closeto the armatureand have suchspring tension as .to. bias the are a mature toward the polepiece 5, sothat always following the rotation of the armature in a counterclockwisedirection toward the pole piece 6, the armature"returnsinto assoclationwith the pole piece 5, or it may be entirely a magnetic bias. In thepresent illustration this latter method has been illustrated. The stops76+76 are provided to prevent the associated armatures from being movedout oi. the :magnetic influence of the pole piece 1 -withwhich they areshown to be associated.

In the circuit arrangementsof Fig. 1, the relay 21 is located on thetiesat the immediate right of the trackway ata suitable distance fromthe highway crossing C, at which it is desired to initiate the operationofthesignal 13, while the relay 21, which functionsto stop the operationof thesignal, islocated beyond the hi ghwaycrossing at which the signalB islocated .andata :point where it is desired thatithe operation of thesignalB be discontinued. Y r 7 Referring now to Fig. 5, the equipmentforcausingthe operation-of relays 21 and22 will be briefly described.This'equipmentf merely consists of an electromagnet 75' suspended from avehicle of a train and so located as to pass in inductive relation tothe polarized trackside relays such as 21 and 22, as the train passesover the points along the trackway at whichthese relays. are located.The polarity of the electromagnet is such that the armature 24 and 23will be caused to rotate in a counter clockwise direction. v

With the foregoing facts in mind, it will now be assumed that a train isapproaching the highway crossing C from the direction indicated by thearrow. When the electromagnet passes over the magnetic pickup elements 1and 2 of relay 21 the armature 24 is rotated in a counter-clockwisedirection out of association'with pole piece 4 and into association withpole piece 3. Owing to the mag netic characteristics of relay 21, ashereinbefore described, the armature 24 remains in association with thepole piece 3 and with its associated contacts even after theelectromagnet 75 has moved out of the inductive field of the magneticpickup elements 1 and 2. A. circuit is now completed from the battery20, through conductor 25, contact and armature 24, conductor27, and thebell B, to the other pole of the battery 20. The bell B thereforeoperates.

As soon as the electromagnet passes into inductive relation with themagnetic pickup elements of the relay 22, the armature 23 will rotate ina counter-clockwise direction and engage its contacts for the periodonly during which the electromagnet 7 5 is in inductive relation withthe magnetic pickup ele ments of this relay. During this period acircuit for the armature restoring coil 28 of the relay 21 is completedwhich extends as follows: from battery 20, through the conductor 25, thewinding 28, conductor 26, the armature 23 and contact of the magnet 22,conductor 28, and to the other pole of the battery 20'. The winding 28is therefore effective to restore the armature 24 to its originalposition into association with the pole piece 4, thereby breaking theformerly traced circuit to the bell B and causingit to cease operation.

In the circuit arrangements of Fig. 2, the relays 32 and 38, like therelay 22 of Fig. 1, are biased, so that their armatures after beingrotated in a counter-clockwise direc tion, always immediately returninto association with their respective pole pieces 7 and 8. The relay31, however, is like the relay 21Iof Fig. 1, its armature 34 alwaysremaining in association with either of the pole pieces. As the trainapproaches the vicinity of the crossing C, the electromagnet 7 5 firstpasses over the magnetic pickup elements of the relay 38. The armature39 momentarily responds and encounters its contact during the periodduring which the electromagnet 75 remains in inductive relation with thepickup elements of this relay to complete a circuit for winding 45 onpole piece 9 of relay 31. This circuit extends from the battery 30,through conductor 36, armature 39 and its contact, conductor 37, branch37, the winding 45 and to the other pole of the battery 30. Since,however, the armature 34 is already associated with the pole piece 9 thecompletion of this circuit at this time is without effect.-

As the elec romagnet '75 passes over the magnetic pickup elements of therelay 31 the armature 34 is rotated in a counter-clockwise direction andengages its associated contact. The armature 34 therefore completes acircuit for the crossing signal B which may be traced as follows: fromthe battery 30, through the conductor 36, contact and armature 34, theconductor 35, and through the bell B to the opposite pole of thebattery. The bell B is therefore set in operation. After the highwaycrossing C has been passed the electromagnet 75 passes over the magneticpickup elements of the relay 32 to momentarily rotate the armature 33 ofthe relay 32 into engagement with its contact, thereby momentarilycompleting a circuit for the armature reset coil 45 of the relay 31.This circuit extends from one terminal of the battery 30, through thearmature 33 and its contact, conductor 37, branch 37, winding 45, and tothe. other terminal of the battery 30. The winding 45 is thereforeeffective to restore the armature 34 into association with its polepiece 9, thereby breaking the formerly traced circuit to the bell B,which consequently ceases operation. If occasion should arise whereinthe train, instead of proceedin past the crossing, stops and backs upafter the operation of the bell B has once been started, the bell willbe stopped by the electromagnet 7 5 passing over the magnetic pickupelements of the relay 38 which will momentarily complete the formerlytraced circuit thru the reset coil 45 to cause the armature 34 torestore and open the circuit of the bell B.

In the circuit arrangements of Fig. 3, arranged for single-line working,the opera tion of the bell at the crossing 0 must be initiated by theapproach of trains from either direction. To accomplish this, two relays42 and 44 having operating characteristics iden tical to those of therelay 21 are provided; while the two relays 41 and 43 have thecharacteristics of the relay 22 of Fig. 1.

When the train approaches the crossing C from the right theelectromagnet 44 rotates its armature in a counter-clockwise rection inassociation with its contacts, thereby completing a circuit for the bellB which extends as follows: from a terminal of battery 40, throughconductor 53, the armature and contact of relay 44, the conductor 53,conductor 50, through the bell B to the other for the reset coil ofrelay 61.

terminals of the battery 40. The bell B is therefore set into operation.

As the electromagnet 7 5 passes over the magnetic pickup elements of therelay 41 the armature 10 of this relay momentarily rotates intoengagement with its contact, thereby completing a reset circuit throughthe winding 46 of relay 44. This circuit extends from the battery 40,conductor 53, through the reset winding 46 of relay 44, the conductor49, the branch 49, through the contact and armature 10 of relay 41, andconductor 51, to the other terminal of the battery 40. The armature ofrelay 44 is therefore rotated back into engagement with its pole piece11. The circuit of the bell B is therefore broken, and this belltherefor-e ceases operation.

Since the control circuits and apparatus for causing the operation andcessation of operation of the bell B by trains approaching from theopposite direction are duplicates to those traced, a description of theremainder of the apparatus and circuits of this arrangement isconsidered unnecessary.

The circuit arrangement shown in Fig. 4 is specifically alternative tothe one shown in Fig. 1, but the principles involved may equally well beapplied to any of the other figures. In this circuit arrangement therelay 62 corresponds to the relay 22 of Fig. 1, while the relay 61corresponds to the relay 21 of Fig. 1. This circuit arrangement utilizesa normally energized line relay 65 which, if deenergized for any reason,completes the circuit of the crossing signal bell B When anelectromagnet passes over the magnetic pickup elements of the relay 61the armature 64 of this relay rotates in a counter-clockwise directionand opens the circuit of the line relay 65. This circuit normallyextends from one terminal of the battery 76, through the conductor 69,the armature 64 and its contact, the conductor 72, and through thewinding of the relay 65 to the other terminal of the battery 76. It willtherefore be obvious that when the armature 64 rotates in a counterclockwise direction this circuit is broken and the armature of relay 65engages'its associated contact, thereby completing a circuit extendingfrom one terminal of the battery 76,

over conductor 71, through the armature and control of relay 65, theconductor 67 and through the bell B and conductor 68 to the otherterminal of the battery 76, causing this bell to operate.

After the train passes the highway crossing C and the electromagnet 7 5'passes over the magnetic pickup elements of relay 62, the armature 63momentarily completes a circuit This circuit estends from a terminal ofthe battery 76, through the conductor 69, the winding of the reset coil70. conductor 66, contacts and armature 63 of the relay 62, to the otherterminal of the battery 76. The armature 64 is therefore irestored toagain complete the formerly traced circuit for the relay 65. Relay 65therefore again lifts its armature, thereby interrupting the tracedcircuit for the bell B Although in the description and showing it isassumed that the train equipment consists of an elect-romagnet, ifdesired, a permanent magnet may be used.

From'the foregoing it will be appreciated that applicants havedevisedmeans of a very simple and reliable character for the control ofrailway crossing signals or the like.

Vvhat is considered new and is desired to have protected by LettersPatent is set forth in the appended claims.

IVhat is claimed is:

1. In combination with a device for giving a warning when a train isapproaching a crossing, a track relay having an armature and twoassociated pole pieces and having means for magnetically biasing itsarmature into association with either pole-piece to which it is moved, acircuit for said device including normally open contacts on saidarmature, vehicle carried means for transmitting a magnetic impulse tosaid relay to cause the same to actuate and complete said circuit, andmeans including a second vehicle controlled relay for causing said firstrelay to again actuate its armature to again open the circuit of saiddevice.

2. In combination with a railway signal, a relay operable by magnetismdirectly transmitted to it from a passing vehicle to actuate saidsignal, a. winding for restoring said relay to cause the actuation ofsaid sig nal to cease, and another relay operative responsive to animpulse transmitted by such passing vehicle to complete a circuitthrough said winding, for the purpose set forth.

3. In combination with a section of railway, a wayside signal, aplurality of relays distributed along the section, vehicle-carried meansfor directly inductively transmitting operating impulses to said relaysas the vehicle passes through the section, a circuit for said signalclosed by the second relay encountered by said vehicle-carried meansirrespective of the direction of movement of the vehicle, and arestoring circuit for said second relay closed by the first or thirdrelay depending upon the subsequent direction of movement of thevehicle.

4. In combination with a device for giving a warning when a train isapproaching a crossing, a two-position relay arranged to remain ineither position to which it is operated, means on a passing vehicle fortransmitting magnetic flux from the vehicle directly to said relay toactuate the same to bring about the operation of said device, and asecond relay momentarily operative responsive to said means on thepassing vehicle to cause the restoration of said first relay and theconsequent cessation of operation of said device. 7

In witness whereof, I hereunto subscribe my name this 26th day ofSeptember, A. D.

ALFRED E. HUDD. In Witness whereof, I hereunto subscribe my name this26th day of September, A. D.

HARRY E. HERSHEY.

